E2: Neuromuscular process of muscular contractions Flashcards
when can a skeletal muscle contract?
when stimulated by electrical impulses from a CNS
what are motor neurones?
-specialised cells that transmit nerve impulses from the CNS in the brain and spinal cord to the muscle fibres
-the nerve that connects to the muscle fibre
Whats the CNS made up of?
-cell body
-axons
-motor end plate
where is the cell body located?
in the spinal cord
where is the cell body located?
in the spinal cord
what do axons do?
branch off the cell body and send impulses to the motor end plates
whats a motor end plate?
where the action potential from an action travels to stimulate a muscle
what makes up a motor unit?
motor neurone + muscle fibres
-a motor neurone provides muscle fibres with a signal
whats the synapse inbetween the motor neurone and the muscle fibre called?
Neuromuscular junction
what happens to a signal when it comes to the end plate of a motor neurone?
the impulse crosses the junction to activate the muscle fibre
what is a synapse?
a connection point between 2 neurones
What is the nuromuscular junction?
-a synapse between motor neurone and muscle fibre
-converts electrical impulses into electrical activity in the muscle fibre.
What is a neurotransmitter?
a chemical messanger in the body, their job is to transmit signals from nerve cells to target cells(muscle fibre)
what is a acetylcholine?
a chemical transmitter/neurotransmitter that is responsible for muscular contraction
what is action potential?
the electrical impulse that makes the muscle contract
what is the flow diagram of the neuromuscular process of muscular contractions?
nervous impulse->
arrives at the neuromuscular junction->
acetylcholine is released->
action potential allows for muscle fibre to contract->
Muscle fibre contracts.
what happens to the signal when it is received by the muscle fibre?
the signal is spread throughout the muscle fibre/myofibril in order for the whole muscle fibre to contract.
when can action potential be made?
when there is enough acetylcholine
true or false: motor neurones cause contractions of a number of different muscle fibres
true
what is the name of the tubes that the signal travels down to reach the filaments/myofibril?
T-tubules